An integrated welded joint thrust chamber structure

Abstract

The present application relates to a kind of integrated welding connection's thrust chamber structure, combustion chamber inner wall and nozzle inner wall are connected by electron beam welding, combustion chamber outer wall and nozzle outer wall are respectively welded with connecting ring, realize the welding connection of combustion chamber and nozzle extension section, combustion chamber cooling channel and nozzle cooling channel are directly communicated, through the ring cavity in the middle, the function of flow equalization is realized, fuel collector is welded on combustion chamber, fuel inlet flange is used as fuel inlet, welded on fuel collector.The present application cancels nozzle inlet collector, layout is compact, simple structure, reduces the overall weight of thrust chamber.

Description

Technical Field

[0001] This invention belongs to the field of aerospace design technology and relates to an integrated welded thrust chamber structure. Background Technology

[0002] The thrust chamber is the device in a liquid rocket engine that converts energy to generate thrust, and it is one of the key components of a liquid rocket engine. The thrust chamber mainly consists of the nose section, the combustion chamber, and the nozzle extension section. The propellant is atomized and injected in the nose section, and then combusted in the combustion chamber to produce high-temperature, high-speed gas. The gas is accelerated by the contracting and expanding nozzle extension section, converting the chemical energy of the propellant into the kinetic energy of the gas, thereby generating huge thrust.

[0003] Currently, the thrust chamber and combustion chamber of hydrogen-oxygen rocket engines are connected by flanges. Both the combustion chamber and the nozzle extension are equipped with collectors and flanges, which are not only heavy, but also require separate pipelines to introduce propellant into the collectors, making the layout relatively complex.

[0004] Therefore, it is necessary to propose a thrust chamber design with a simpler structure to simplify the layout and reduce weight. Summary of the Invention

[0005] The technical problem solved by this invention is to overcome the shortcomings of the prior art and propose an integrated welded thrust chamber structure. Compared with the prior art, it realizes the welded connection between the combustion chamber and the nozzle extension section, and the combustion chamber cooling channel and the nozzle cooling channel are directly connected. The structure is simple, the layout is compact, and the overall weight of the thrust chamber is reduced.

[0006] The solution of the present invention is:

[0007] An integrated welded thrust chamber structure includes a head, a combustion chamber, a nozzle extension section, a fuel inlet flange, a nozzle outlet flange, a nozzle outlet pipeline, a head inlet flange, and a fuel collector.

[0008] The combustion chamber includes an inner wall and an outer wall. The inner wall of the combustion chamber has a milled groove structure with a combustion chamber cooling channel. The nozzle extension section includes an inner wall and an outer wall, with the inner wall of the nozzle also having a milled groove structure with a nozzle cooling channel. A mating boss extends from the inner wall of the combustion chamber and the inner wall of the nozzle at their joints, and the two mating bosses are connected by electron beam welding. The connecting ring is a T-shaped ring forging, and the outer wall of the combustion chamber and the outer wall of the nozzle are connected to the connecting ring by electron beam welding. After the inner wall of the combustion chamber is welded to the inner wall of the nozzle, the outer wall of the combustion chamber, the outer wall of the nozzle, and the connecting ring, an annular cavity is formed in the middle, which is used for fuel flow equalization.

[0009] The head is welded to the combustion chamber; the tail of the nozzle extension section is connected to one end of the nozzle outlet pipeline through the nozzle outlet flange, and the other end of the nozzle outlet pipeline is connected to the head through the head inlet flange; the fuel collector is welded to the combustion chamber, and the fuel inlet flange serves as the fuel inlet and is welded to the fuel collector.

[0010] Preferably, the fuel collector is located close to the nozzle extension.

[0011] Preferably, the direction of the butt weld between the inner wall of the combustion chamber and the inner wall of the nozzle is perpendicular to the generatrix of the inner wall of the combustion chamber.

[0012] Preferably, the mating bosses on the inner wall of the combustion chamber and the mating bosses on the inner wall of the nozzle are designed with a thickening, with a thickening amount of 0.5 to 1 mm.

[0013] Preferably, the connection point between the inner wall mating boss and the combustion chamber cooling channel is rounded.

[0014] Preferably, the connection point between the nozzle inner wall mating boss and the nozzle cooling channel is rounded.

[0015] Preferably, the outer wall of the combustion chamber and the connecting ring are connected by electron beam welding as follows:

[0016] The outer wall of the combustion chamber is machined with an outer wall locking boss at the joint between the outer wall and the connecting ring. The bottom of the connecting ring is directly inserted into the outer wall locking boss and then connected by electron beam welding.

[0017] Preferably, the inner wall of the combustion chamber is made of copper alloy material, and the outer wall of the combustion chamber is made of GH4169 or high-strength steel material.

[0018] Preferably, the inner and outer walls of the nozzle are made of the same stainless steel material.

[0019] Preferably, when the thrust chamber is working, all the fuel enters the fuel collector from the fuel inlet flange. Then, a portion flows counter-currently upward along the combustion chamber cooling channel to cool the combustion chamber, while the other portion flows downstream after being uniformly distributed in the annular cavity, cooling the nozzle extension section along the nozzle cooling channel. The fuel cooling the nozzle extension section enters the head inlet flange through the nozzle outlet flange, along the nozzle outlet pipeline, and then enters the head fuel chamber to merge with the fuel cooling the combustion chamber. Finally, all of the fuel participates in the chemical reaction to generate thrust.

[0020] The advantages of this invention compared to the prior art are:

[0021] (1) The present invention designs an integrated welded thrust chamber structure, which connects the combustion chamber and the nozzle extension section by welding. The structure is simple and can effectively reduce the weight of the thrust chamber.

[0022] (2) The protrusion at the joint between the inner wall of the combustion chamber and the inner wall of the nozzle extension section is locally thickened to ensure the strength of the inner wall at the joint. At the same time, after welding, the inner wall of the combustion chamber and the inner wall of the nozzle transition smoothly, avoiding the ablation problem caused by the presence of steps;

[0023] (3) The combustion chamber cooling channel and the nozzle extension section cooling channel of the present invention are directly connected. The nozzle extension section eliminates the inlet collector. The fuel enters the annular cavity formed by the connecting ring, which can further improve the flow uniformity, simplify the flow path, improve the compactness of the thrust chamber layout, and reduce the overall weight of the thrust chamber. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the overall structure and flow path;

[0025] Figure 2 A partial view of the welded connection between the combustion chamber and the nozzle. Detailed Implementation

[0026] The invention will now be further described with reference to the accompanying drawings.

[0027] This invention provides an integrated welded thrust chamber structure, such as... Figure 1 As shown, the structure mainly includes a head 1, a combustion chamber 2, a nozzle extension section 3, a fuel inlet flange 4, a nozzle outlet flange 10, a nozzle outlet pipeline 20, and a head inlet flange 30.

[0028] The head 1 is welded to the combustion chamber 2, and the combustion chamber 2 is welded to the nozzle extension section 3 via a connecting ring 48. The tail end of the nozzle extension section 3 is connected to one end of the nozzle outlet pipe 20 via the nozzle outlet flange 10, and the other end of the nozzle outlet pipe 20 is connected to the head 1 via the head inlet flange 30. The fuel collector 5 is welded to the combustion chamber 2, and the fuel inlet flange 4 serves as the fuel inlet and is welded to the fuel collector 5.

[0029] like Figure 2 The diagram shows a partial view of the welded connection between the combustion chamber and the nozzle extension section. The combustion chamber 2 mainly consists of two parts: the inner wall 42 and the outer wall 41. The inner wall 42 is a milled groove structure with a combustion chamber cooling channel 50. The nozzle extension section 3 mainly consists of two parts: the inner wall 44 and the outer wall 45. The inner wall 44 is a milled groove structure with a nozzle cooling channel 51.

[0030] The inner wall 42 of the combustion chamber is typically made of a copper alloy with good thermal conductivity, while the inner wall 44 of the nozzle is typically made of stainless steel. Both the inner wall 42 and the inner wall 44 extend a short section at their joint, forming a joint boss 55 on the inner wall of the combustion chamber and a joint boss 56 on the inner wall of the nozzle. The extension length of the two bosses is approximately 2–3 mm. They are typically connected using electron beam welding to form a butt weld 43 between the inner wall of the combustion chamber and the inner wall of the nozzle, with the weld direction perpendicular to the generatrix of the inner wall of the combustion chamber. To ensure the weld quality of the butt weld 43 between the inner wall of the combustion chamber and the inner wall of the nozzle, both the joint boss 55 and the joint boss 56 are thickened, with a thickness of approximately 1.5 mm–2 mm and an increase in thickness of approximately 0.5–1 mm. To reduce stress concentration, the joint bosses 55 and 56 are rounded at their connection to the cooling channel, with a radius typically R1–2 mm.

[0031] The outer wall of the combustion chamber 41 is typically made of high-strength GH4169 or high-strength steel (S-06 or S-03). The outer wall of the nozzle 45 is typically made of the same stainless steel as the inner wall of the nozzle 44. The connecting ring 48 is typically made of the same material as the outer wall of the combustion chamber 41 and is a T-shaped forging. The outer wall of the combustion chamber 41 and the outer wall of the nozzle 45 are respectively electron beam welded to the connecting ring 48, forming a butt weld 49 between the connecting ring and the outer wall of the combustion chamber and a butt weld 46 between the connecting ring and the outer wall of the nozzle. To ensure the effective connection strength of the weld between the outer wall of the combustion chamber 41 and the inner wall of the combustion chamber 42, a short section of a locking boss 60, approximately 5 mm long and 1 mm thick, is retained on the outer wall of the combustion chamber 42. The bottom of the connecting ring 48 is directly inserted into the locking boss 60 of the outer wall of the combustion chamber.

[0032] After the combustion chamber inner wall 42 is welded to the nozzle inner wall 44, the combustion chamber outer wall 41, the nozzle outer wall 45, and the connecting ring 48, an annular cavity 47 is formed in the middle. To ensure the strength of this cavity, the axial length of the annular cavity 47 is controlled between 4 and 6 mm. The fuel flowing downstream enters the annular cavity 47 along the combustion chamber cooling channel 50. After being evenly distributed here, it enters the nozzle cooling channel 51 and finally flows into the head fuel chamber.

[0033] When the thrust chamber is working, the fuel flow direction is as follows: Figure 1 As indicated by the middle arrow, all fuel enters the fuel collector 5 from the fuel inlet flange 4. A portion flows upstream along the combustion chamber cooling channel 50 to cool the combustion chamber 2, while the other portion flows downstream along the nozzle cooling channel 51 to cool the nozzle extension section 3. The fuel cooling the nozzle extension section 3 passes through the nozzle outlet flange 10, along the nozzle outlet pipe 20, and enters the head inlet flange 30. It then enters the head fuel chamber and merges with the fuel cooling the combustion chamber 2, ultimately participating entirely in the chemical reaction to generate thrust.

[0034] This invention designs an integrated welded thrust chamber structure. The inner wall of the combustion chamber is connected to the inner wall of the nozzle by electron beam welding, and the outer wall of the combustion chamber and the outer wall of the nozzle are respectively welded to the connecting ring, realizing the welded connection between the combustion chamber and the nozzle extension section. The cooling channel of the combustion chamber is directly connected to the cooling channel of the nozzle. Through the middle annular cavity, the flow equalization function is realized. At the same time, the nozzle inlet collector is eliminated, resulting in a compact layout, simple structure, and reduced overall weight of the thrust chamber.

[0035] The parts of this invention not described in detail are common knowledge to those skilled in the art.

Claims

1. An integrally welded joint thrust chamber structure, characterized by: The head, the combustion chamber, the nozzle extension section, the fuel inlet flange, the nozzle outlet flange, the nozzle outlet pipeline, the head inlet flange and the fuel collector; The combustion chamber comprises a combustion chamber inner wall and a combustion chamber outer wall, wherein the combustion chamber inner wall is a milled structure with combustion chamber cooling channels; the nozzle extension section comprises a nozzle inner wall and a nozzle outer wall, wherein the nozzle inner wall is a milled structure with nozzle cooling channels; the combustion chamber inner wall and the nozzle inner wall each extend with an abutment boss at the abutment position; the two abutment bosses are connected by electron beam welding; the connecting ring is a T-shaped ring forge piece; the combustion chamber outer wall and the nozzle outer wall are connected to the connecting ring by electron beam welding; after the combustion chamber inner wall, the nozzle inner wall, the combustion chamber outer wall, the nozzle outer wall and the connecting ring are welded, a ring cavity is formed in the middle, which is used for fuel flow equalization; The head is connected to the combustion chamber by welding; the tail of the nozzle extension section is connected to one end of the nozzle outlet pipeline through the nozzle outlet flange, and the other end of the nozzle outlet pipeline is connected to the head through the head inlet flange; the fuel collector is welded to the combustion chamber, and the fuel inlet flange is welded to the fuel collector as a fuel inlet; The combustion chamber outer wall and the connecting ring are connected by electron beam welding as follows: The combustion chamber outer wall and the connecting ring are connected by electron beam welding as follows:

2. The integrally welded thrust chamber structure of claim 1 wherein: The fuel collector is located close to the nozzle extension section.

3. The integrally welded thrust chamber structure of claim 1 wherein: The abutment weld of the combustion chamber inner wall and the nozzle inner wall is perpendicular to the parent line of the combustion chamber inner wall.

4. The integrally welded thrust chamber structure of claim 1 wherein: The abutment bosses of the combustion chamber inner wall and the nozzle inner wall are thickened by 0.5-1mm.

5. The integrally welded thrust chamber structure of claim 1 wherein: The abutment boss of the combustion chamber inner wall is connected to the combustion chamber cooling channel with a round corner.

6. The integrally welded thrust chamber structure of claim 1 wherein: The abutment boss of the nozzle inner wall is connected to the nozzle cooling channel with a round corner.

7. The integrally welded thrust chamber structure of claim 1 wherein: The combustion chamber inner wall is made of copper alloy, and the combustion chamber outer wall is made of high-strength steel.

8. The integrally welded thrust chamber structure of claim 1 wherein: The nozzle inner wall and the nozzle outer wall are made of the same stainless steel.

9. The integrally welded thrust chamber structure of claim 1 wherein: When the thrust chamber is working, all the fuel enters the fuel collector from the fuel inlet flange, then part of the fuel flows upward along the combustion chamber cooling channel to cool the combustion chamber, and the other part of the fuel flows downward along the nozzle cooling channel after flow equalization in the ring cavity; the fuel for cooling the nozzle extension section enters the head inlet flange from the nozzle outlet flange along the nozzle outlet pipeline, then enters the head fuel cavity to combine with the fuel for cooling the combustion chamber, and finally all the fuel participates in chemical reaction to generate thrust.

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